AGRICULTURAL  EXPERIMENT  STATION 

BENJ.  IDE   WHEELER,  President 

COLLEGE    OF    AGRICULTURE  thomas  forsyth  hunt,  dean  and  director 

H.  E.  VAN    NORMAN,  Vice-Director  and  Dean 
University  Farm  School 


UNIVERSITY  OF  CALIFORNIA 

IE    OF   AGRIC 

BERKELEY 


CIRCULAR  No.  134. 

(July,  1915) 

CONTROL  OF  RAISIN  INSECTS. 

By  Frederic  T.  Bioletti 

Introduction.  Raisins,  like  other  stored  food  products,  are  liable 
to  attack  from  various  insects,  several  of  which,  under  favorable  con- 
ditions, are  capable  of  doing  great  damage. 

This  damage  is  usually  less  common  or  noticeable  in  California  than 
in  the  eastern  states  or  other  regions  where  the  raisins  are  stored  for 
a  considerable  time  in  the  hands  of  distributors  or  retailers.  This  is 
because  the  bulk  of  the  raisin  crop  in  California  usually  passes  from 
the  field  through  the  packing  houses  and  into  the  hands  of  the  buyer 
during  the  cooler  part  of  the  year,  when  the  activities  and  reproductive 
powers  of  the  insects  are  at  their  lowest  ebb. 

When  raisins  are  stored  for  many  months  even  in  California,  and 
especially  during  the  warmer  part  of  the  year,  the  insects  may  become 
very  numerous  and  cause  considerable  losses.  In  packing  houses, 
running  continuously  and  receiving  raisins  from  different  sources,  this 
is  apt  to  occur. 

Certain  measures  are  adopted  by  most  of  the  packers  in  an  effort 
to  prevent  this  damage.  The  use  of  cleaning  machines  and  fumigation 
with  bisulfid  of  carbon  are  the  chief  among  them.  That  these  measures, 
as  usually  carried  out,  are  not  completely  successful  is  shown  by  many 
samples  of  "wormy  raisins"  received  at  the  Experiment  Station,  to- 
gether with  complaints  of  the  lack  of  efficiency  of  the  control  measures 
used.  These  complaints  have  been  more  numerous  than  usual  during 
the  last  two  years,  indicating  the  advisability  of  an  investigation  of  the 
trouble  and  of  the  causes  of  the  failures  in  control. 

By  the  courtesy  of  a  raisin-packing  company,  we  were  furnished 
with  all  necessary  facilities  for  making  this  investigation,  which  was 
carried  out  by  the  Division  of  Viticulture  with  the  advice  and  assist- 
ance of  the  Division  of  Entomology. 

In  August,  1912,  the  work  was  placed  in  the  hands  of  Mr.  L.  J. 
Nickels.  Mr.  Nickels  made  observations  on  the  life  history  and  habits 
of  the  principal  injurious  species  and  on  the  usual  methods  of  control, 
and  devised  methods  which  gave  promise  of  overcoming  the  trouble. 
That   they   have   done   so   where   applied   is  shown   by   the   following 

1— 1839G 


extract  from  a  letter  received  on  March  2,  1915,  from  the  president  of 
the  company  in  whose  packing  houses  the  investigation  was  made : 

"Regarding  the  advice  given  by  your  department,  following 
their  investigations  concerning  the  control  of  insect  pests  in 
raisins,  I  beg  to  say  that  we  have  followed  this  advice  with  marked 
success  and  have  had  no  complaints  whatever  from  goods  to  which 
the  bisulfid  process  has  been  applied,  though  we  have  applied  it 
to  several  hundred  carloads  all  told,  during  the  last  two  seasons." 

In  order  that  other  packers  who  fail  to  prevent  completely  the  insect 
infestation  of  their  raisins  may  be  able  to  adopt  more  efficient  methods 
this  summary  account  is  published.  It  is  based  on  the  observations 
and  recommendations  of  Mr.  Nickels  so  far  as  these  appear  to  be  of 
immediate  practical  interest.  The  figures  and  cuts  were  all  prepared 
bv  Mr.  Nickels. 


Fig.    1.     Raisin   Worms.      {Larva    of   Plodia.) 
NATURE    OF    THE   INJURY. 

Raisins  which  have  been  stored  for  some  time  without  special  pre- 
cautions usually  become  "wormy."  The  so-called  worms  are  the  larvae, 
caterpillars  or  grubs  of  certain  moths  or  beetles.  The  most  common 
and  troublesome  of  these  is  the  Indian  Meal  Moth  (see  Fig.  2).  This 
moth  may  be  seen  flying  around  and  in  raisin-packing  houses.  It  lays 
its  eggs   on   exposed  raisins,   especially   on   silk  threads  spun  by  the 


larvae.  In  the  sweat  boxes,  the  eggs  are  most  numerous  near  the  sides. 
On  packed  raisins,  the  eggs  are  deposited  where  cracks  allow  access. 

The  larvae  hatching  from  the  eggs  grow  slowly  to  their  full  size  of 
one-half  to  five-eighths  of  an  inch  in  length  (see  Pig.  1).  These 
"worms"  vary  in  color  from  grayish  white  to  shades  of  pink  and 
green. 

When  the  larvae  reach  full  size  they  enter  the  pupal  stage.  For  this 
purpose  they  surround  themselves  with  a  network  of  silk  threads  to 
which  pellets  of  excrement  are  often  added.  They  remain  in  this 
resting  condition  for  about  sixteen  days  at  an  average  summer  tem- 
perature of  80  degrees  Fahrenheit.  The  time  is  longer  at  lower  tem- 
peratures, more  than  twice  as  long  at  70  degrees  Fahrenheit.  It  is 
probable  that  the  insect  passes  the  winter  in  this  stage,  but  in  warm 
situations  the  larvae  may  live  over  the  winter. 


Fig.    2.     Indian   Meal    Moth    (adult). 

The  adult  or  moth  emerges  from  the  pupa  and  lives  on  the  average 
about  one  week.  They  are  plentiful  only  in  summer  and  autumn  and 
do  not  breed  in  the  winter. 

The  Fig  Moth  is  very  similar  in  appearance  and  habits  to  the  Indian 
Meal  Moth.  It  has  been  found  attacking  raisins,  but  is  much  less 
abundant. 

Another  insect,  the  Saw-toothed  Grain  Beetle,  often  causes  "wormy" 
raisins,  but  is  much  less  troublesome  than  the  moth. 

The  larvae  or  "worms"  are  yellowish  white,  slender  and  somewhat 
flattened  (see  Fig.  3).  They  are  much  smaller  than  the  moth  larvae, 
only  about  one-eighth  of  an  inch  long  when  full  grown.  They  pupate 
in  a  delicate  cocoon  formed  of  fragments  of  their  food  and  excrements. 

The  adult  is  a  small  beetle  about  one-tenth  of  an  inch  long  and 
about  one-quarter  as  wide  (see  Fig.  4) . 
2—18396 


The  adult  beetles  live  much  longer  than  the  moths  and  are  present 
throughout  the  year.  Attention  to  the  prevention  of  the  increase  and 
spread  of  this  insect  is  therefore  necessary  at  all  seasons. 

Another  beetle,  the  Bust  red  Flour  Beetle,  has  been  found  in  small 
numbers  attacking  raisins. 


Fig.   3.      Saw-toothed   Grain 
Beetle  (Larva) 

SUGGESTIONS   FOR   CONTROL. 

The  observations  of  Mr.  Nickels  indicate  clearly  that  much  can  be 
done  to  diminish  the  damage  due  to  insect  attacks  on  raisins  by  slight 
modifications  of  the  present  practices  in  packing  houses.  They  appear 
to  show,  moreover,  that  by  somewhat  greater  modifications  and  the 
use  of  simple,  inexpensive  devices  and  measures,  the  infestation  can 
be  completely  prevented  until  the  raisins  leave  the  hands  of  the  packers. 
They  can  thus  be  delivered  to  the  retailer  in  perfect  condition  and 
remain  sound  on  his  hands  much  longer  than  is  at  present  usual. 
Complete  protection  under  all  conditions  can  be  obtained,  probably, 
only  by  the  use  of  insect  proof  packages.  Attempts  have  been  made 
to  devise  such  a  package,  but  while  some  are  promising,  none  has  yet 
been  demonstrated  to  be  completely  successful. 

The  commencement  of  the  infestation  of  a  packing  house  is  due  to 
insects  brought  in  on  raisins  from  the  vineyard  or  from  other  places 
where  they  have  been  stored.  The  insects  brought  in  from  the  vineyard 
are  comparatively  few  in  number.     The  great  abundance  of  insects  in 


certain  seasons  is  due  partly  to  the  accumulation  of  insects,  due  to  the 
cleaning  machinery,  and  partly  to  the  multiplication  of  these  insects  in 
the  packing  house.  The  cleaning  machinery  removes  nearly  all  the 
moths  and  beetles,  in  their  various  stages,  from  the  raisins,  but  most 
of  them  are  allowed  to  escape,  to  breed  and  to  infest  other  raisins. 
The  refuse  of  stems  and  inferior  raisins  allowed  to  accumulate  in  and 
around  the  packing  house,  and  occasionally  the  stores  of  raisins  allowed 


Fig.  4. 


The  Saw-toothed  Grain  Beetle 
(adult). 


to  stay  in  the  packing  house  for  weeks  or  months  often  favor  the 
abundant  multiplication  of  the  insects  collected  by  the  cleaning 
machines. 

The  first  thing  to  be  done,  therefore,  is  to  catch  and  destroy  the 
insects  removed  by  the  machinery.  This  can  be  done  to  a  great  extent 
by  a  modification  of  the  box  used  to  catch  the  refuse.  This  refuse 
seems  to  be  the  principal  source  of  reinfestation.  In  some  cases,  insects 
in  large  numbers  have  been  observed  leaving  the  refuse.  Few  insects 
apparently  are  injured  by  the  cleaning  machinery.  Many  of  the  small 
beetles  reach  even  the  cap  stemmer  and  escape  from  its  refuse  box. 
To  prevent  this  a  simple  trap  has  been  devised. 

It  consists  of  a  movable  frame,  having  on  its  under  side  a  pad  of 
cloth  which  is  to  be  saturated  with  coal  oil  or  crude  carbolic  acid. 
This  pad  extends  beyond  the  inner  edge  of  the  box.     It  is  protected 


from  falling  refuse.  Insects  cannot  crawl  out  of  the  box.  The  frame 
is  easily  removable  when  it  is  desired  to  .empty  the  box.  The  cloth 
pad  should  be  moistened  often  enough  to  exercise  its  full  deterrent 
powers.     The  contents  of  the  box  should  be  burned. 


INSECT  TRAP  FOR  REFUSE  BOX. 

A  section  and  perspective  view  of  this  box  is  shown  in  Fig.  5.  B  is 
the  refuse  box,  A  is  a  frame  composed  of  four  boards.  This  is  to  be 
made  just  large  enough  to  slip  over  the  outside  of  the  box.  From  the 
top  of  this  box-encircling  frame,  another  set  of  four  boards,  B,  is  made 
to  slope  downward  at  an  angle  of  45  degrees  and  extend  over  the  inner 
edge  of  the  box.  These  boards  should  be  at  least  six  inches  wide.  All 
joints  should  be  accurately  fitted  and  the  four  corners  should  be 
reinforced  with  iron.  Upon  the  under  side  of  D  is  placed  a  pad  of 
cloth,  C,  at  least  four  inches  wide,  extending  three  or  more  inches 
beyond  the  inner  edge  of  B.  The  inner  edge  of  B  should  be  beveled 
to  fit  D.  The  frame  A  D  C  is  not  to  be  fastened  to  B,  but  merely  rests 
upon  it  so  as  to  be  easily  removed  when  the  box  is  emptied. 

Other  insects  which  escape  or  do  not  pass  through  the  machinery 
may  be  caught  in  trap  boxes  containing  a  few  refuse  raisins.  These 
boxes  are  placed  in  convenient  places  in  various  parts  of  the  packing 
house.  Wandering  insects  will  take  refuge  in  them  and  can  be  killed 
by  fumigation  or  by  burning.  These  boxes  should  be  fumigated  or 
disinfected  with  live  steam  at  least  once  a  month  to  prevent  breeding, 
and  the  raisin  bait  removed. 

All  refuse  of  stems  and  spoiled  raisins  in  and  around  the  packing 
house  on  which  the  insects  could  multiply  should  be  cleaned  up  regu- 
larly and  destroyed.  This  is  especially  necessary  during  the  breeding 
season,  which  extends  from  about  the  middle  of  March  to  the  middle 


of  September.  All  refuse  should  be  cleaned  up  immediately,  if  pos- 
sible, and  in  any  case  a  complete  cleaning  up  should  take  place  once 
a  week. 

These  methods  carried  out  carefully  would  in  most  cases  so  diminish 
the  numbers  of  insects  in  the  packing'  house  that  fumigation  of  the 
packed  raisins  might  often  be  unnecessary. 

More  perfect  control  of  the  insects  could  be  obtained  by  methods 
aiming  at  the  complete  prevention  of  multiplication  in  both  vineyard 
and  the  packing  house.  A  method  suggested  by  Mr.  Nickels  and 
Professor  Woodworth  promises  to  accomplish  this  end  very  effectively. 
It  is  based  principally  on  so  arranging  the  storage  of  the  raisins  that 
the  vineyards  are  kept  free- from  anything  on  which  the  insects  could 
feed  for  a  sufficient  length  of  time  to  insure  their  death  from  starvation, 
and  to  keep  the  packing  house  free  from  anything  on  which  they  could 
breed  long  enough  to  insure  their  extermination  on  the  death  of  the 
adults.  This  method,  generally  carried  out,  should,  in  connection 
with  the  other  control  measures,  insure  the  raisins  from  all  injury  by 
either  the  raisin  moth  or  beetle. 

By  the  first  of  May,  all  raisins  should  be  removed  from  the  vineyard 
to  the  packing  house.  There  will  then  be  nothing  in  the  vineyard  on 
which  the  insects  could  feed  or  breed.  When  the  new  crop  is  made, 
therefore,  it  will  be  clean,  as  there  is  nothing  to  infest  it  with,  if  care 
is  taken  not  to  put  it  in  contact  with  dirty  sweat  boxes  or  other  infested 
material. 

When  the  new  crop  goes  into  the  packing  house,  the  methods  already 
recommended  will  prevent  any  infestation  during  the  first  part  of 
the  packing  season.  During  the  months  of  October,  December  and 
January,  there  is  rarely  any  emergence  of  adult  insects  or  increase 
of  larvae  and  the  raisins  may  be  stored  either  in  the  packing  house  or 
in  the  vineyard,  except  when  the  packing  house  is  heated,  in  which 
case  they  should  be  held  outside  where  the  temperature  is  low.  About 
February  1st,  however,  the  packing  house  should  be  clear  of  all  stored 
raisins  and  a  thorough  annual  cleaning  up  would  be  advisable. 

During  February,  March  and  April,  the  packing  house  should  be 
kept  as  free  from  raisins  as  possible,  only  enough  being  accepted  as  is 
necessary  for  current  needs.  No  raisins  should  be  kept  in  the  packing 
house  longer  than  four  days  during  these  three  months.  This  will 
insure  the  removal  by  the  cleaning  process  and  the  destruction  before 
hatching  of  all  eggs  that  may  be  laid  by  any  adults  which  have  survived 
the  winter,  or  emerged  from  pupae  remaining  in  the  packing  house  or 
brought  in  from  outside.  All  these  adults  will  have  died  before  the 
end  of  April,  and,  in  May,  any  raisins  remaining  in  the  vineyards 
should  be  removed  to  the  packing  house. 


8 

FUMIGATION  WITH   CARBON-BISULFIDE. 

However  carefully  preventive  measures  are,  carried  out,  raisins  may 
occasionally  become  infested  and  curative  measures  will  be  necessary. 
Such  measures  are  almost  always  necessary  under  ordinary  conditions. 
All  infestation  can  be  destroyed  by  proper  fumigation  with  carbon- 
bisulfide.  This  fumigation  is  perhaps  best  used  as  a  measure  of  pre- 
caution in  all  cases  where  raisins  are  shipped. 

Carbon-bisulfide  fumigation  is  in  fact  used  in  most  packing  houses, 
but  often  without  satisfactory  results,  even  in  some  cases  with  large 
amounts  and  prolonged  treatment. 

Investigation  showed  that  cases  of  failure  were  easily  explained  by 
a  lack  of  a  sufficiently  air-tight  fumigating  room.  Where  there  was 
any  considerable  leakage,  20  pounds  of  carbon-bisulfide  per  each  1,000 
cubic  feet  was  found  insufficient.  When  the  room  was  made  thoroughly 
air-tight,  10  pounds  was  found  to  give  perfect  results  if  applied  prop- 
erly. The  boxes  of  raisins  should  be  packed  loosely  and  the  carbon- 
bisulfide  placed  in  shallow  dishes  near  the  ceiling.  The  room  should 
be  kept  closed  for  at  least  twenty-four  hours,  for  this  time  was  found 
necessary  to  kill  the  beetles.  The  moths  were  killed  in  twelve  hours  and 
eggs  in  sixteen. 

In  constructing  a  fumigating  room,  air-tightness,  non-inflammability, 
and  convenience  should  be  considered.  The  fumigating  rooms  should 
be  located  so  that  both  unstemmed  raisins  and  the  packed  product  may 
be  readily  trucked  to  them  for  treatment.  Fumigation  chambers 
should  not  be  located  close  to  railroad  tracks  nor  boiler  rooms. 

Construction  of  Fumigating  Boom.  Concrete  is  the  only  material 
which  can  be  recommended  for  the  construction  of  fumigating  rooms. 
Where  several  tons  of  raisins  are  packed  a  day,  two  rooms  are  necessary. 
The  doors  of  the  fumigating  rooms  should  open  away  from  the  packing 
house  and  swing  towards  each  other. 

A  letter  from  Mr.  E.  F.  Mohrhardt,  secretary  of  the  Fire  Under- 
writers of  the  Pacific,  contains  valuable  suggestions  to  the  prospective 
builder. 

(Copy.) 

Board  of  Underwriters  of  the  Pacific, 
814  Merchants  Exchange  Building, 

San  Francisco,  December  12,  1913. 
Mr.  Leslie  J.  Nickels, 

Department  of  Entomology,  Berkeley,  Cal. 
Dear  Sir  :  Your  favor  of  the  10th  is  received,  expressing  your  desire 
for  information  regarding  the  best  construction  of  fumigating  rooms 
in  which  carbon  bi-sulfide  may  be  used,  in  order  to  properly  inform 
the  raisin  packers  of  the  state. 

Our  experience  in  this  connection,  as  a  result  of  the  investigation  of 
the  engineering  department  of  the  board,   is  that  fumigating  rooms 


z 


~C3F~ 


10 

inside  packing  houses  should  be  strongly  opposed;  no  method  of  con- 
struction can  remove  the  danger. 

We  have  made  an  overhead  charge  of  1  per  cent  to  the  rate  of  insur- 
ance, and  where  these  rooms  have  been  maintained  in  the  packing 
house  the  increase  in  rate  has  practically  eliminated  them  therefrom. 
Should  it  be  the  intention  to  have  such  rooms  in  the  packing  plant, 
they  should  be  constructed  preferably  of  concrete,  with  door  opening 
outside,  and  so  arranged  that  an  explosion  would  act  through  the  door 
to  the  open  air.  Construction  of  wood  with  tar  paper,  or  of  wood 
with  wire  lath  and  cement  finish,  should  not  be  advocated. 

I  might  add  that  the  addition  to  rate  above  quoted  is  applicable  to 
buildings  of  all  classes  of  construction. 

Trusting  the  information  given  may  prove  of  value  to  you, 
Yours  truly, 

(Signed)     E.  F.  Mohrhardt, 

Secretary. 

The  Board  of  Fire  Underwriters  will  gladly  furnish  any  information 
at  their  disposal  in  regard  to  the  construction  of  fumigating  rooms. 

A  room,  twenty  feet  long,  fourteen  feet  wide  and  seven  feet  high, 
will  hold  about  ten  tons  of  raisins.  With  any  other  length  and  breadth, 
the  height  of  the  room  should  not  be  increased.  No  windows  or  lights 
should  be  in  the  room.  The  door  should  be  thick  and  constructed  with 
beveled  edges  padded  to  prevent  the  escape  of  gas. 

The  door  of  a  fumigating  room  should  be  constructed  like  the  door 
of  an  ice-chest.  It  should  be  not  less  than  four  and  one-half  feet  wide 
in  the  narrowest  part  and  six  and  one-half  feet  high.  It  should  be 
lined  with  some  gas-tight,  fire  proof  material;  sheet  asbestos  is  very 
good.  Top  and  sides  of  the  door  should  be  beveled  and  padded  with 
canvas.  The  door  should  be  painted,  swung  with  very  substantial 
hinges  and  fastened  with  an  ice-box  latch.  Provision  should  be  made 
for  locking  the  door  during  periods  of  fumigation. 

Since  trucks  must  pass  in  and  out  through  the  door,  a  beveled  sill 
would  be  difficult  to  cross  and  furthermore  would  soon  be  destroyed. 

A  method  of  making  the  door  tight  is  shown  in  Fig.  6. 

On  the  floor  near  the  bottom  of  the  door  A  is  placed  a  movable  bar 
C  which  is  held  in  place  by  the  stationary  blocks  B  B.  Two  or  four 
sides  of  the  bar  may  be  padded  with  canvas.  The  bar  is  placed  so  that 
canvas  comes  next  to  the  floor  and  door. 

As  the  door  A  is  closed,  the  wedges  D,  fastened  upon  A,  one  braced  by 
E,  force  the  padded  bar  C  to  the  floor  and  in  turn  (A)  closing  upon  C 
(padded  portion)  makes  a  gas-tight  junction.  When  the  door  (A)  is 
opened  and  the  bar  C  removed,  passage  in  and  out  is  not  obstructed. 

The  Amount  of  Carbon  Bisulfide  to  Use.  As  a  rule,  fumigate  raisins 
before  packing.  Use  ten  pounds  of  carbon  bisulfide  to  every  one  thou- 
sand cubic  feet  of  space  to  be  fumigated.     No  allowance  should  be 


11 

made  in  the  quantity  of  bisulfide  used  according  to  whether  the  fumi- 
gating chamber  is  full  of  raisins  or  not.  As  low  as  only  25  per  cent 
of  the  available  air  space  may  be  occupied  by  solid  material  when  the 
chamber  is  full  of  raisins  in  sweat  boxes. 

The  bisulfide  should  be  placed  in  shallow  dishes  upon  the  top  of  the 
raisins.  Use  as  many  dishes  as  possible.  Continue  the  fumigation 
twenty-four  hours.  Save  any  remaining  carbon  bisulfide.  This  dosage 
was  found  to  kill  all  stages  of  the  insects  found  at  Fresno  in  sweat 
boxes ;  also  in  fifty-pound  bulk  boxes  pressed  and  packed  without  paper, 
providing  there  were  cracks  in  the  covers  of  these  boxes,  at  least  one- 
sixteenth  of  an  inch  wide.  Insects  were  placed  amongst  raisins  packed 
loose  in  cartons,  the  cartons  were  nailed  up  in  boxes.  Slight  cracks 
occurred  along  the  edges  of  these  boxes.  They  were  placed  so  that  the 
longest  dimension  of  the  cartons  extended  horizontally.  With  the  above 
dosage  all  forms  of  life  in  the  cartons  were  killed.  Thompson  Seedless 
was  the  only  variety  of  raisins  treated,  but  there  is  no  reason  to  believe 
that  the  method  of  fumigation  adopted  would  prove  less  successful  with 
other  varieties. 


STATION  PUBLICATIONS  AVAILABLE  FOR  DISTRIBUTION. 


Appendix   to    Viticultural 


REPORTS 

1897.     Resistant   Vines,    their   Selection,    Adaptation,    and   Grafting. 

Report  for  1896. 
1902.     Report  of  the  Agricultural  Experiment  Station  for  1898-1901. 
1908.     Report  of  the  Agricultural  Experiment  Station  for  1901-03. 
1904.     Twenty-second  Report  of  the  Agricultural  Experiment  Station  for  1903-04. 
1914.    Report   of   the   College   of  Agriculture  and  the  Agricultural  Experiment  Station,    July, 

1913- June,  1914. 


BULLETINS. 


No. 

168.  Observations    on    Some    Vine    Diseases 

in  Sonoma  County. 

169.  Tolerance  of  the  Sugar  Beet  for  Alkali. 

170.  Studies  in  Grasshopper  Control. 
174.  A  New  Wine-Cooling  Machine. 

177.  A    New    Method    of   Making    Dry    Red 

Wine. 

178.  Mosquito  Control. 

182.  Analysis     of    Paris    Green    and    Lead 

Arsenate.     Proposed  Insecticide  Law. 

183.  The  California  Tussock-Moth. 

184.  Report    of    the    Plant    Pathologist    to 

July  1,   1906. 

185.  Report  of   Progress   in   Cereal  Investi- 

gations. 
195.  The  California  Grape  Root-worm. 

197.  Grape  Culture  in  California;  Improved 

Methods      of      Wine-making;     Yeast 
from   California   Grapes. 

198.  The  Grape  Leaf-Hopper. 

203.  Report    of    the    Plant    Pathologist    to 
July  1,  1909. 

207.  The  Control  of  the  Argentine  Ant. 

208.  The  Late  Blight  of  Celery. 

211.  How   to    Increase   the    Yield   of   Wheat 

in   California. 

212.  California  White  Wheats. 


No. 
213. 
216. 


220. 
225. 
227. 
230. 
234. 
241. 
242. 
243. 

244. 
246. 
248. 

249. 
250. 
251. 


252. 
253. 


254. 
255. 


The  Principles  of  Wine-making. 

A    Progress    Report    upon    Soil     and 

Climatic      Factors      Influencing      the 

Composition  of  Wheat. 
Dosage  Tables. 

Tolerance  of  Eucalyptus  for  Alkali. 
Grape  Vinegar. 
Enological  Investigations. 
Red  Spiders  and  Mites  of  Citrus  Trees. 
Vine  Pruning  in  California.     Part  I. 
Humus  in  California  Soils. 
The  Intradermal  Test  for  Tuberculosis 

in  Cattle  and  Hogs. 
Utilization  of  Waste  Oranges. 
Vine  Pruning  in  California.     Part  LT. 
The  Economic  Value  of  Pacific  Coast 

Kelps . 
Stock  Poisoning  Plants  of  California. 
The  Loquat. 

Utilization    of    the    Nitrogen    and    Or- 
ganic   Matter   in    Septic   and   Lmhoff 

Tank  Sludges. 
Deterioration  of  Lumber. 
Irrigation    and   Soil   Conditions   in   the 

Sierra  Nevada  Foothills,  California. 
The  Avocado  in  California. 
The  Citricola  Scale. 


CIRCULARS. 


No. 
65.  The  California  Insecticide  Law. 

69.  The  Extermination  of  Morning-Glory. 

70.  Observations    on    the    Status    of    Corn 

Growing  in  California. 
76.  Hot  Room  Callusing. 

79.  List  of  Insecticide  Dealers. 

80.  Boys'  and  Girls'  Clubs. 

82.  The     Common     Ground     Squirrels     of 

California. 

83.  Potato   Growing  Clubs. 
87.  Alfalfa. 

8S.  Advantages  to  the  Breeder  in  Testing 
his  Pure-bred  Cows  for  the  Register 
of  Merit. 

91.  Disinfection  on  the  Farm. 

92.  Infectious    Abortion     and    Sterility    in 

Cows. 

100.  Pruning  Frosted  Citrus  Trees. 

101.  Codling    Moth    Control    in    the    Sacra- 

mento Valley. 

106.  Directions    for   using   Anti-Hog  Cholera 

Serum. 

107.  Spraying  Walnut  Trees  for  Blight  and 

Aphis    Control. 

108.  Grape  Juice. 


No. 
109. 


110. 
111. 

113. 
114. 
115. 

117. 

118. 
119. 
121. 

122. 

123. 

124. 
125. 
126. 
127. 
128. 
129. 
130. 


Community  or  Local  Extension  Work 
by  the  High  School  Agricultural  De- 
partment. 

Green  Manuring  in  California. 

The  Use  of  Lime  and  Gypsum  on  Cali- 
fornia Soils. 

Correspondence  Courses  in  Agriculture. 

Increasing  the  Duty  of  Water. 

Grafting  Vinifera  Vineyards. 

The  Selection  and  Cost  of  a  Small 
Pumping  Plant. 

The  County  Farm  Bureau. 

Winery  Directions. 

Some  Things  the  Prospective  Settler 
Should  Know. 

The  Management  of  Strawberry  Soils 
in  Pajaro  Valley. 

Fundamental  Principles  of  Co-opera- 
tion in  Agriculture. 

Alfalfa  Silage  for  Fattening  Steers. 

Aphids  on  Grain  and  Cantaloupes. 

Spraying  for  the  Grape  Leaf-Hopper. 

House  Fumigation. 

Insecticide  Formulas. 

The  Control  of  Citrus  Insects. 

Cabbage   Growing  in   California. 


